Hi Allison,
What are you wanting to buy? Acrobat.com subscriptions are available in various countries. Please see: Countries where ExportPDF is available for purchase and Countries where PDF Pack is available for purchase
You just need to log in to the appropriate Adobe Store, by clicking Change Location in the lower-left corner of the Adobe.com website. You will need to have an email address and credit card with an address in the same country from which you purchase the subscription.
I hope that helps!
Best,
Sara